OpenStax, Precalculus 2e §7.2 Sum and Difference Identities · Exercise 45 · Trigonometry · Compound & multiple angles
Sum and Difference Identities · Exercise 45
Find the exact value algebraically, and then confirm the answer with a calculator to the fourth decimal point.
OpenStax, Precalculus 2e · §7.2 Sum and Difference Identities · Exercise 45
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